Stabilization of Heavy Metal Containing Smelting Ash through Mechano-Chemical Reaction

Abstract

The present study described the application of mechano-chemical reaction on stabilization of heavy metal containing smelting ash. Extraction procedure for leaching toxicity test showed that the leaching toxicity of cadmium and lead in smelting ash decreased very significantly after grinded. The optimal condition of the mechano-chemical stabilization process was established as follow. The ball milling medium was stainless steel, the additive was the mixture of elemental sulfur and iron powder, the dosage of additive was n(Cd):n(Fe):n(S)=1:3:3, and ball milling time was 3.5 hour. The results showed that the leaching toxicity of cadmium decreased from 2496 mg/L to 0.43 mg/L, compared to lead decreased from 7.30 mg/L to 0.12mg/L under the optimal condition.